It is particularly preferred to employ Staphylococcal genes and gene products as targets for the development of antibiotics. The Staphylococci make up a medically important genera of microbes. They are known to produce two types of disease, invasive and toxigenic. Invasive infections are characterized generally by abscess formation effecting both skin surfaces and deep tissues. S. aureus is the second leading cause of bacteremia in cancer patients. Osteomyelitis, septic arthritis, septic thrombophlebitis and acute bacterial endocarditis are also relatively common. There are at least three clinical conditions resulting from the toxigenic properties of Staphylococci. The manifestation of these diseases result from the actions of exotoxins as opposed to tissue invasion and bacteremia. These conditions include: Staphylococcal food poisoning, scalded skin syndrome and toxic shock syndrome.
A Blast P search result of publicly available sequence data, using the amino acid sequence of the invention as a query sequence, revealed a Streptococcus mutans homologue, which is a GTP-binding protein (ERA, sp/P42182/BEX_BACSU BEX PROTEIN).
Clearly, there is a need for factors that may be used to screen compounds for antibiotic activity, such as novel ERA of the invention. These factors may also be used to determine their roles in pathogenesis of infection, dysfunction and disease. There is a further need for identification and characterization of such factors and their antagonists and agonists which can play a role in preventing, ameliorating or correcting infections, dysfunctions or diseases.
The polypeptides of the invention have amino acid sequence homology to a known Streptococcus mutans GTP-binding protein ERA protein.